Hardware. Drivers. Missing WebGL support in the browser. One of these. Any two of these. All of these.

Seriously: "Linux platforms like Ubuntu" means absolutely nothing in terms of capability. Hardware comes first and your end user absolutely needs support for hardware-accelerated GL in order to have hardware accelerated GL. OpenGL is not a software library. Drivers come second; even if the hardware supports it, your end user must have a compatible device driver in order to enable this support. If these two core requirements are not met, there's no point in even continuing. Third for WebGL is whether or not the end user is using a browser that has WebGL support.

To analyze these problems more you really need to start describing what kind of problems are happening, and determine configuration information about the end user systems that are having these problems. Otherwise we're doing the equivalent of sticking pins in a map in the dark.

Hardware. Drivers. Missing WebGL support in the browser. One of these. Any two of these. All of these.

What mhagain said.

So how do you go about diagnosing that? For starters, run "glxinfo" and post the output of that command in a follow-up post inside of [code]...[/code] tags. This will give you a quick view of what GPU and GPU drivers you have installed, along with their capabilities.